Vacuum casting silicone, a type of RTV-2 silicone, encompasses both tin-cured silicone and platinum-cured silicone. These silicone materials boast exceptional properties, including high tear resistance, corrosion resistance, high fidelity, and excellent mold release characteristics. Typically, after the master model is crafted, RTV-2 silicone is employed to create silicone molds. This silicone is ideal for vacuum casting and can be quickly molded at room temperature, making it ideal for small batch production of products.

Rapid prototyping is the first step in validating product feasibility. It serves as a direct and effective way to identify flaws, shortcomings, and disadvantages in the design of a product, thereby facilitating targeted improvements to address these defects.

vacuum casting silicone

Vacuum Casting: First, a master model is made by CNC machining or 3D printing, which is used to make the corresponding silicone mold, and then the liquid material is injected into the cavity of the silicone mold in a vacuum chamber to produce a replica of the master model. This process is suitable for casting small products.

Reaction Injection Molding: Reaction injection molding is a product prototype processing technology used for rapid mold creation. It involves the rapid injection of a two-component polyurethane material into the mold cavity under ambient temperature and low pressure, leading to the formation of the product through chemical and physical processes such as polymerization, cross-linking, and curing. This technique is suitable for the production of large and medium-sized plastic casings.

Vacuum Casting Materials: ABS-like general-purpose resin, Glass-filled nylon-like, Elastomeric TPE-like, PC-like (polycarbonate) , Translucent or water-clear casting urethane (PMMA-like), POM-like or PU-like.

Features

Technical Parameter

Product NameColorHardnessMixing RatioViscosityPot LifeCure TimeTear Strength
RTV-3130 tinWhite30 A100A:3B24,000 cps35 mins12 hrs≥23.0 N/mm
RTV-3140 tinWhite38 A100A:3B25,000 cps35 mins12 hrs≥19.0 N/mm
RTV-3230 tinTranslucent30 A100A:3B24,000 cps35 mins12 hrs≥24.0 N/mm
RTV-3240 tinTranslucent37 A100A:3B25,000 cps35 mins12 hrs≥20.0 N/mm
RTV-4140 platinumTranslucent40 A1A:1B21,000 cps40 mins8 hrs≥17.0 N/mm
RTV-4150 platinumTranslucent50 A1A:1B33,000 cps40 mins10 hrs≥6.0 N/mm
RTV-5240 platinumTransparent40 A10A:1B90,000 cps60 mins18 hrs≥14.0 N/mm
rtv-2 silicone

Application Examples

Vacuum casting silicone is extensively harnessed in the realm of product development for the meticulous replication of small batches, particularly adept for slender-walled prototypes such as television sets, other domestic appliances, mobile phones, telephone casings, and an array of communication devices. Its capacity to forge models of extraordinary detail with unparalleled surface finesse makes it ideal for limited production runs of end-use products, finding widespread application in diverse sectors like medical instrumentation, electronics, robotics, automotive, household gadgets, cosmetics, and beyond.

Automotive Components: Dashboards, knobs, instruments, emblems, engine hood ornaments, intake manifolds, and other automobile accessory prototype models.

Consumer Electronics: Casings, controllers, user interface panels, sensor integrations, etc.

Other Uses: Medical models, exhibition display models, robotic casings, scientific instruments, musical instruments, sporting equipment accessories.

Attention

Please use the same models of A and B components. If mixing different models of A and B components, first test a small amount to verify feasibility.

It is advisable to conduct a small-scale test application to evaluate whether the silicone material is suitable for your specific project, particularly when its performance is in question.

When using condensation-cure silicone, it's important to seal the curing agent immediately after use to prevent air exposure. Air can cause hydrolysis in the tin catalyst, leading to a film or crust formation on its surface. Avoid using a hydrolyzed catalyst, as this can result in the silicone not curing properly.

rapid prototyping silicone

For addition-cure silicone, the platinum catalyst is especially prone to deactivation if contaminated. To ensure effective curing, avoid exposing it to water, impurities, smoke, tin catalysts, acids, bases, and any substances with sulfur, phosphorus, nitrogen, or organic compounds. These elements can significantly hinder the silicone's curing process.

Safety

The curing agent in the B component of tin-cure silicone may emit odors, hence it is advisable to conduct operations in a well-ventilated setting. In cases of inadequate ventilation, it is imperative to don respiratory protective gear. Should any discomfort arise during handling, one must promptly relocate to an area abounding in fresh air. Avoid splashing the material in the eyes, but if this happens, flush immediately with plenty of water and seek medical attention.

rtv-2 silicone for vacuum casting

Platinum-cured silicone is considered non-toxic and odorless and is safe for contact with human skin. However, wearing disposable waterproof gloves is still a good recommendation for ease of handling and cleaning.

A very small number of people may be allergic to uncured liquid silicone, if attached to the skin, please wipe with a rag as soon as possible, and then rinse with soapy water.

We do not recommend liquid silicone for children under the age of 16. Although many of our liquid silicone materials are considered "non-toxic", they are still liquid chemicals and can cause irritation. It is especially important for children to be supervised by an adult when working with chemicals to ensure their safety. Please ensure to store both silicone and curing agents out of children's reach and adhere to the pertinent safety guidelines.

Storage

At temperatures of 15°C-25°C ( 60°F-77°F), tin-cured silicone can usually be stored for 10-12 months, platinum-cured silicone (translucent) can usually be stored for at least 12 months, and platinum-cured silicone (transparent) can be stored for up to 12 months. However, storing materials at higher temperatures may result in a shorter shelf life for unused materials. Exceeding the specified storage time does not necessarily mean that the product cannot be reused. However, in such cases, to ensure quality and performance, it is recommended that the material be retested to verify that it is still suitable for the intended use.

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